This research from India suggests that mental health conditions such as OCD could be treated using drugs that target the immune system.  This is consistent with PANDAS, which is when strep antibodies attack the brain due to a quirk in the patient’s immune system.  Researchers in the States have long known the immune system is a key component in the disorder, but identifying a drug to target that problem is a new development.

https://www.nationalheraldindia.com/international/antibodies-may-provide-a-new-treatment-for-ocd?fbclid=IwAR3rr2ZvdFAqQd9c5znZ5rZmOk-RsJJHgMSFmz3kbNbzXxv2HDuxPrG7Wns#l86hpsjlsm4by12eypq